1. Field of the Invention
The present invention relates to a time reception apparatus and a wave clock.
2. Description of Related Art
Time information, a low frequency standard-time and frequency-signal broadcast (hereinafter simply referred to as a “standard frequency broadcast”) including time information, i.e. a time code, is currently broadcasted in each country of Japan, United States, Germany and the like. As a kind of a time reception apparatus to receive the standard frequency broadcast, a wave clock which corrects a counting time has been put into practical use.
Moreover, as a technique for preventing the false detection of the time information owing to noise components intermixed into a reception signal, there is known a technique of judging the waveform of the reception signal by sampling a demodulation result of the reception signal and smoothing the demodulated signal, and of detecting the time information (see JP 2003-222687A). To put it concretely, a period of the data transmitted in every second (second data) is divided into a plurality of sections at the time of coding a received standard frequency broadcast, and the sampling of each of the divided sections is performed. When the pieces of the same sampled data can be acquired by a predetermined number or more, the section is judged to be “High” or “Low.” Then, the second data is coded based on a combination pattern of the judgment results of the respective sections.
However, according to the technique disclosed in the JP 2003-222687A, when a combination pattern of the judgment results of “High” or “Low” in the plurality of sections in a period of the second data does not agree with any predetermined combinations, the second data is judged to be an error. Consequently, the technique has a problem of the impossibility of the detection of time information when the reception state of the time information is bad and a lot of noises are included in a reception signal.
The present invention was made in consideration of the problem in earlier development, and it is an object of the present invention to make it possible to detect time information appropriately even if noise components are much included in a reception signal.